System and methods for addition of beneficial agricultural, biological, and/or dedusting additives to granular fertilizers

ABSTRACT

Methods and related systems for conditioning of granular fertilizers post-manufacture to reduce the generation of dust during handling, transport, and storage of the fertilizers, and/or to increase the agricultural benefits of the fertilizer. The method includes introducing a quantity of an aqueous conditioning agent, such as by spraying, to a plurality of fertilizer granules. The aqueous conditioning agent can include one or more beneficial agricultural and/or dedusting additives including one or more acidifying agents, one or more drying agents, one or more herbicides and/or pesticides, one or more chelating agents, one or more biological agents, and combinations thereof.

RELATED APPLICATIONS

The present application is a national phase entry of PCT Application No.PCT/US2014/051662, filed Aug. 19, 2014, which claims the benefit of U.S.Provisional Application No. 61/867,334 filed Aug. 19, 2013, and U.S.Provisional Application No. 61/968,328 filed Mar. 20, 2014, each ofwhich is incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

The present invention is directed to a system and related method ofreducing dust generated during handling, transporting, and storage ofgranulated fertilizer. Specifically, the present invention is directedto a system and related method for conditioning the granular fertilizerby a water-based treatment or aqueous conditioning agent for reducingdust generation and/or for the addition of beneficial agricultural,biological, and/or dedusting additives.

BACKGROUND OF THE INVENTION

Agricultural inorganic fertilizers typically include a base comprisingat least one of three primary inorganic nutrients—nitrogen (N),phosphate (P), and potassium (K). These fertilizers are identified bytheir NPK rating in which the N value is the percentage of elementalnitrogen by weight in the fertilizer, and the P and K values representthe amount of oxide in the form of P₂O₅ and K₂O that would be present inthe fertilizer if all the elemental phosphorus and potassium wereoxidized into these forms. The N—P—K proportions or concentration varyacross fertilizer types and user needs.

For example, the base fertilizer can comprise a phosphate fertilizer(such as monoammonium phosphate (“MAP”), diammonium phosphate (“DAP”)),a potash fertilizer (such as muriate of potash (“MOP”)) or otherpotassium-based fertilizer, or a nitrogen-based fertilizer such as afertilizer containing urea. The fertilizers can also include anycombination of secondary nutrients and/or micronutrients. The secondarynutrients can include sulfur compounds, calcium, and/or magnesium, andthe micronutrients can include iron, manganese, zinc, copper, boron,molybdenum, and/or chlorine. The micronutrients and/or secondarynutrients can be added to solution in their elemental form, or ascompounds, such as a salt.

Many of these agricultural fertilizers are granulated, dried, andtreated with dust control agents after formulation to provide thefertilizer in a stable and easily handled form. An inherent drawback ofthe conventional granulation process is that a significant portion ofthe fertilizer may generate dust particulates either during manufacture,storage, or in distribution, which is significantly more difficult tohandle and distribute on the fields to be treated. In addition towasting otherwise useful fertilizer, the fertilizer may createundesirable fugitive particle emissions. Fugitive particulate emissionscan be mitigated, but in certain conditions mitigation costs can becomeuneconomical.

To reduce the dust generation, the fertilizer granules are often coatedwith an anti-dust coating that reduces or entraps the dust createdduring the granulation or transport. The anti-dust coating can comprise,for example, petroleum, wax, or other oil-based liquids that are sprayedonto the fertilizer granules to adhere any dust particulates formed,during granulation or transport, for example, to the larger fertilizergranules. The coating also encapsulates the dust particulates to preventor inhibit the dust particulates from becoming airborne.

While traditional coatings are effective at controlling the dustparticulates, the inherent drawback of these coatings is that thecoatings have a limited effective shelf-life and can have diminishingeffectiveness as the coating ages. Prolonged storage or transport of thecoated fertilizer can present a greater safety risk as the storage ortransport time may have exceeded the effective life of the coatingresulting in unsafe fertilizer products, and/or undesirable flowcharacteristics in storage bins, transportation equipment, and fieldapplication equipment. Furthermore, these traditional coatings canpotentially add significant cost to the end-product due to the cost ofthe coating composition and/or increased manufacturing costs.Alternative dedusting agents with extended shelf life are commerciallyavailable but these products tend to have substantially higher cost andfor this reason have not been broadly adopted by the industry.

As such, there is a need for a means of efficiently and effectivelyreducing dust generated during the handling of granular fertilizersand/or to increase the agricultural benefits of the fertilizer.

SUMMARY OF THE INVENTION

The present invention is directed to a method and related system forconditioning of granular fertilizers post-manufacture to reduce thegeneration of dust during handling, transport, and storage of thefertilizers, and/or to increase the agricultural benefits of thefertilizer. The method includes introducing a quantity of an aqueousconditioning agent, such as by spraying, to a plurality of fertilizergranules having a surface temperature of about 50° F. to about 250° F.,and more particularly about 130° F. to about 200° F., and a crudemoisture content of about 0 to about 6.5 weight percent (wt %), moreparticularly from about 0.5 wt % to about 3 wt % and more particularlyfrom about 0.5 wt % to about 1.5 wt %, in a conditioning vessel. Theaqueous conditioning agent can comprise water only or a water-basedsolution in the form of liquid, steam, and/or superheated steam, andwith or without beneficial agricultural and/or dedusting additives. Theaqueous conditioning agent is introduced at a temperature of about 32°F. to about 800° F. depending on the form of the agent, and moreparticularly from about 70° F. to about 170° F. when the agent is in theform of water, with or without beneficial agricultural and/or dedustingadditives.

Alternatively, one or more beneficial agricultural and/or dedustingadditives are introduced onto the surface of the granules separate fromthe aqueous conditioning agent (with or without additives). The one ormore additives can be added simultaneously or in series with the aqueousconditioning agent.

As mentioned above, the aqueous conditioning agent can optionallycontain one or more beneficial agricultural and/or dedusting additives,such as, for example, but not limited to, one or more acidifying agents(e.g., but not limited to, citric acid, sulfuric acid, phosphoric acid,sulfamic acid, and combinations thereof), one or more drying agents(e.g., but not limited to, corn starch, and/or wheat starch), and/or oneor more chelating agents (e.g., but not limited to,ethylenediaminetetraacetic acid (EDTA), polyethylenimine (PEI)), orcombinations thereof, in an amount of about 0.01 wt % to about 99.99 wt% of solution (i.e. weight of solute/weight of solution), and moreparticularly from about 0.01 wt % to about 20 wt % of solution forcertain applications, from about 20 wt % to about 50 wt % of solutionfor other applications, and from about 50 wt % to about 99.99 wt % foryet other applications.

In an alternative embodiment of the invention, in addition to or as analternative to the additives listed above, the aqueous conditioningagent can contain one or more beneficial agricultural additives selectedfrom one or any combination of secondary nutrients and/or micronutrientsin an amount of about 0.01 wt % to about 99.99 wt % of solution, andmore particularly from about 20 wt % to about 50 wt % of solution. Thesecondary nutrients can include sulfur compounds, calcium, and/ormagnesium, and the micronutrients can include iron, manganese, zinc,copper, boron, molybdenum, and/or chlorine. The micronutrients and/orsecondary nutrients can be added to solution in their elemental form, oras compounds, such as a salt.

In yet other embodiments, in addition to or as an alternative to theadditives listed above, the aqueous conditioning agent can contain oneor more beneficial agricultural additives selected from one or anycombination of herbicides and/or pesticides.

In addition to or as an alternative to the additives listed above, otherembodiments of the aqueous conditioning agent can comprise one or morebeneficial agricultural additives selected from one or any combinationof biological material. In some aspects, the biological materials, or“biologicals,” can comprise, for example, one or more biologicalchemicals, plant and other extracts, microbial agents, and/or otherliving organisms. In some embodiments, the biological material cancomprise microorganisms, including, but not limited to, bacteria such asBacillus, Rhizobium, Azobacter, and Azospirillum, fungi such asAspergillus, Mycorhizzae, Beauveria, Metarhizium, and Trichoderma,and/or yeast such as Saccharomyces, Schizosaccharomyces, Sporobolomyces,Candida, Trichosporon, and Rhodosporidium. In other cases, the aqueousconditioning agent can comprise biological materials that are smallmolecule and peptide-based compositions such as, but not limited to,metabolites, peptides, lipopetides, hormones, peptide hormones,siderophores, glycopepetides, humates, surfactants, vitamins, enzymes,amino acids and amino acid derivatives, and nucleic acids and nucleicacid derivatives. In some embodiments, biologicals included inembodiments of the aqueous conditioning agent can be applied tofertilizers or fertilizer granules at a final concentration of about 10³to about 10¹² CFU (colony forming units)/g, and more particularly about10⁶ to about 10⁹ CFU/g. Biologicals applied accordingly have thepotential to enhance the growth and development of plants as well astreat plant diseases.

The granules with aqueous conditioning agent(s) applied thereto are thenoptionally subjected to a mechanical energy exposure, such as in theform of tumbling or mixing, in the conditioning vessel to induce desiredparticle interactions between particles. In an alternative embodiment,the granules and the aqueous conditioning agent are introduced into afluidized bed reactor such that the surface of each individual granuleis subjected to surface conditioning described above, withoutnecessarily being subjected to particle to particle interaction ormechanical energy exposure. In yet another alternative embodiment, thegranules are exposed to a combination of particle to particleinteractions (e.g. tumbling or mixing) and introduced into a fluidizedbed reactor in either order, or in any combination.

The added moisture from the aqueous conditioning agent is removed fromthe granules either naturally or with the application of energy. Thiscan be accomplished in the conditioning vessel itself either during theoptional tumbling and/or after tumbling of the granules. The drying canbe done by drying via a dry airstream (heated or non-heated) such as afugitive dust air stream for removal of water vapor, dust, and air, aheated dryer such as a blower, until a final moisture content of about 0wt % to about 6.5 wt % of the granules is achieved, more particularlyfrom about 0.5 wt % to about 3.0 wt, and even more particularly fromabout 0.5 wt % to about 1.5 wt %, resulting in conditioned fertilizergranules.

The conditioning process can be placed in-line after granulation and/ordrying of the fertilizer granules, or at a remote location, i.e.off-line. For example, the conditioning process can be achieved in awarehouse, separate processing facility, at a transportation site, orany of a variety of locations.

The conditioning of the granular fertilizers by water treatment allowsfor the reduction in application of dust control agents, such as theoil-based coatings described above, thereby reducing raw material costs.Also, reduction in dust generated during distribution from themanufacturer to the grower results in improved industrial hygiene forthe manufacturers, transporters, customers, and/or customer employees,thereby reducing the costs and equipment otherwise needed to mitigatepotential industrial hygiene issues. Finally, when beneficialagricultural additives are incorporated, the conditioned granules canhave increased agricultural benefits compared to unconditioned granules.

The conditioning methods and systems described above are not limited tothe treatment of fertilizer granules. The methods and systems accordingto embodiments can be used on any granular or particular material thathas the propensity to produce unwanted or fugitive dust. Other uses caninclude, for example, the conditioning of coal, feed products such asfeed supplements or pellets, food processing, mining operationsincluding ores and tailings, cured or dried cement, dirt, gravel orsand, waste, asbestos, or any of variety of uses.

The above summary of the various representative embodiments of theinvention is not intended to describe each illustrated embodiment orevery implementation of the invention. Rather, the embodiments arechosen and described so that others skilled in the art can appreciateand understand the principles and practices of the invention. Thefigures in the detailed description that follow more particularlyexemplify these embodiments.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a process flow diagram of a conditioning method according toan embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to FIG. 1, a non-limiting exemplary embodiment of a system andmethod for conditioning fertilizer granules for improved dust controland/or agricultural benefits generally includes the supply of aplurality of fertilizer granules at 102. The fertilizer granules can beunconditioned or can be previously condition in which additionalconditioning is desired or required. The granules are not limited tofertilizer granules, and can comprise any of a variety of granular orparticular materials.

In this non-limiting embodiment, the fertilizer granules can be any of anumber of fertilizer types including, but not limited to inorgranicincluding nitrogen-based (e g ammonium nitrate or urea),phosphorous-based (e.g. phosphate fertilizers including mono-ammoniumand di-ammonium phosphates), potassium-based (e.g. potash or muriate ofpotash) fertilizers, and any of a variety of N—P—K compound fertilizers,with or without secondary nutrients such as sulfur or sulfur compounds,calcium, and magnesium, and/or micronutrients such as iron, manganese,zinc, copper, boron, molybdenum, and chlorine. In one non-limitingembodiment, the fertilizer granules are formed using the granulationmethods described in U.S. Pat. No. 6,544,313 entitled “Sulfur-ContainingFertilizer Composition and Method for Preparing Same,” incorporatedherein by reference in its entirety. In another non-limiting embodiment,the fertilizer granules are formed using the granulation methodsdescribed in U.S. Pat. No. 7,497,891 entitled “Method For Producing AFertilizer With Micronutrients,” incorporated herein by reference in itsentirety.

Depending on the desired temperature and moisture content of thefertilizer granules before application of the aqueous conditioningagent, optional application of heat and/or air 104 may be necessary ordesired. For example, IR heat, gas fired heat, or any of a variety ofheat sources can be applied to the plurality of fertilizer granules todry and/or heat the granules to the target surface temperature and/ormoisture content before application of an aqueous conditioning agent at108. In one embodiment, the target surface temperature of the granulesis approximately about 50° F. to about 250° F., and more particularlyabout 130° F. to about 200° F., and the target moisture content is about0 to about 6.5 weight percent (wt %), more particularly from about 0.5wt % to about 3 wt % and more particularly from about 0.5 wt % to about1.5 wt %

Once the granules are at the target temperature and moisture content,they are placed into a conditioning vessel at 106, such as a tumblingdrum or bed, flighted drum or bed, or fluidized bed for application ofthe one or more aqueous conditioning agents. In one embodiment, theconditioning vessel includes one or more sprayers or nozzles for thespray application of one or more aqueous conditioning agents at 108,with or without beneficial agricultural and/or dedusting additives. Asdiscussed above, the aqueous conditioning agent can comprise water or awater-based solution, in the form of liquid, steam, and/or superheatedsteam, and with or without beneficial agricultural and/or dedustingadditives. The aqueous conditioning agent is introduced at a temperatureof about 32° F. to about 800° F. depending on the form of the agent, andmore particularly from about 70° F. to about 170° F. when the agent isin the form of liquid water or a water-based solution, with or withoutbeneficial agricultural and/or dedusting additives.

As mentioned above, the aqueous conditioning agent can optionallycontain one or more beneficial agricultural and/or dedusting additives,such as, for example, acidifying agents, drying agents, chelatingagents, micronutrients, secondary nutrients, biological materials,pesticides and herbicides.

Acidifying agents can include, but are not limited to, citric acid,sulfuric acid, phosphoric acid, sulfamic acid, and combinations thereof.Drying agents can include, but are not limited to, corn starch, and/orwheat starch. Chelating agents can include, but are not limited to,ethylenediaminetetraacetic acid (EDTA), polyethylenimine (PEI), orcombinations thereof. Any of the agents can be added in an amount ofabout 0.01 wt % to about 99.99 wt % of solution, and more particularlyfrom about 0.01 wt % to about 20 wt % of solution for certainapplications, from about 20 wt % to about 50 wt % of solution for otherapplications, and from about 50 wt % to about 99.99 wt % for yet otherapplications.

In addition to or as an alternative to the additives listed above, theaqueous conditioning agent can contain one or more beneficialagricultural additives selected from one or any combination of secondarynutrients and/or micronutrients in an amount of about 0.01 wt % to about99.99 wt % of solution, and more particularly from about 20 wt % toabout 50 wt % of solution. The secondary nutrients can include, forexample, sulfur compounds, calcium, and/or magnesium, and themicronutrients can include, for example, iron, manganese, zinc, copper,boron, molybdenum, and/or chlorine.

In addition to or as an alternative to the additives listed above, theaqueous conditioning agent can contain one or more beneficialagricultural additives selected from one or any combination ofbiological material. In some cases, biological material, or“biologicals,” can comprise microorganisms, including, but not limitedto, bacteria such as Bacillus, Rhizobium, Azobacter, and Azospirillum,fungi such as Aspergillus, Mycorhizzae, Beauveria, Metarhizium, andTrichoderma, and/or yeast such as Saccharomyces, Schizosaccharomyces,Sporobolomyces, Candida, Trichosporon, and Rhodosporidium. In othercases, the aqueous conditioning agent can comprise biologicals that arenot microorganisms, including, but not limited to, small molecule andpeptide-based compositions such as metabolites, peptides, lipopetides,hormones, peptide hormones, siderophores, glycopepetides, humates,surfactants, vitamins, enzymes, amino acids and amino acid derivatives,and nucleic acids and nucleic acid derivatives.

In some embodiments, biologicals included in embodiments of the aqueousconditioning agent can be applied to fertilizers or fertilizer granulesat a final concentration of about 10³ to about 10¹² CFU (colony formingunits)/g, and more particularly about 10⁶ to about 10⁹ CFU/g 10 ⁶ toabout 10⁹ CFU. For example, 4.1 mls of an aqueous solution comprisingbiologicals can be added to 1 lb of fertilizer, or about 10¹² to about10¹⁵ CFU/L can be added to liquid fertilizer to achieve the above targetconcentration. In some cases, biologicals included in embodiments of theaqueous conditioning agent can be applied at temperatures ranging fromabout 70° F. to about 210° F., or more particularly, from about 70° F.to about 180° F., or more particularly, from about 70° F. to about 160°F. Biologicals applied accordingly have the potential to enhance thegrowth and development of plants as well as treat plant diseases.

In an alternative embodiment, one or more of the beneficial agriculturaland/or dedusting additives described above are optionally introduced at111 onto the surface of the granules separate from the aqueousconditioning agent (with or without additives). The one or morebeneficial agricultural and/or dedusting additives can be addedsimultaneously or in series with (e.g. upstream and/or downstream from)the aqueous conditioning agent, such as by spraying, in conditioningvessel 106.

In one non-limiting embodiment, the aqueous conditioning agent is addedat 108 in an amount of about 0.1 to about 10 wt % of the total weight ofthe fertilizer, and more particularly from about 2.0 to about 4.0 wt %of the total weight of the fertilizer. This can be accomplished, forexample, by the addition of aqueous conditioning agent at a rate ofabout 0 to about 22 gallons per ton of granular fertilizer, and moreparticularly about 5-10 gallons per ton of granular fertilizer,depending on the composition or concentration of the aqueousconditioning agent, and the desired amount of aqueous conditioning agentper granule.

In one embodiment, simultaneously with or after the application of theaqueous conditioning agent at 108, the granules are optionally subjectedto mechanical energy at 110 in the form of agitation, such as shakingand/or tumbling, within the conditioning vessel 106 to promote or inducemechanical interaction between granules. The conditioning vessel canfurther optionally include mixing equipment such as, a ribbon blender,paddle mixer, baffles, and/or can comprise a rotating drum such that theapplication of the aqueous conditioning agent is spread evenly over thegranules, and to further induce mechanical interaction between thegranules.

In an alternative embodiment, the granules and the aqueous conditioningagent are introduced into a fluidized bed reactor such that surfaces ofthe granules are subjected to surface conditioning described above,without necessarily being subjected to particle to particle interactionor mechanical energy exposure. Optionally, one or more beneficialagricultural and/or dedusting additives can be added to the fluidizedbed separately from the aqueous conditioning agent (with or withoutadditives).

During and/or after the optional application of energy at 110, the extramoisture from the application of the aqueous conditioning agent isremoved at 112. In one embodiment, removal of the moisture at 112 can beaccomplished without additional equipment and/or processing. Forexample, a previously established airflow, such as a ventilation meansor duct for removing fugitive dust, water vapor, or other ventilationsuch as a fluid bed dryer, moves air that is sufficiently dry throughvessel 106 to remove the added moisture.

In another embodiment of the invention, one or more gases are suppliedto or moved through the vessel at 114 to remove the added moisture fromthe granules. The one or more gases can be, for example, recycled and/orfresh air, and/or an inert gas such as argon or nitrogen. The gas can becompletely dry, or have a low or negligible moisture content. In aparticular embodiment, the gas includes one or more beneficialagricultural and/or dedusting additives or agents as described above forapplication to the granule surface.

In yet another embodiment, the latent heat of the fertilizer granules issufficient to dry the granules by evaporation of the moisture to thesurrounding atmosphere of the vessel 106. The air of the vessel 106 isremoved and replaced as needed. In yet another embodiment, the granulesare subjected to the application of dry air and/or heat in a separatedrying vessel (not shown), such as a fluid bed dryer. In each of theembodiments, the added moisture is removed until a final moisturecontent of about 0 to about 6.5 weight percent (wt %), more particularlyfrom about 0.5 wt % to about 3 wt % and more particularly from about 0.5wt % to about 1.5 wt % of the granules is achieved, resulting inconditioned fertilizer granules.

The conditioned fertilizer granules are removed at 116 are then shippedto storage and/or end-use customers, or are reconditioned or furtherconditioned or processed as desired.

As discussed above, the conditioning of the granular fertilizers bywater treatment allows for the reduction in application of dust controlagents, such as the oil-based coatings, thereby reducing raw materialcosts and/or manufacturing costs. Also, reduction in dust generatedduring distribution from the manufacturer to the grower results inimproved industrial hygiene for the manufacturers, transporters,customers, and/or customer employees, thereby reducing the costs andequipment otherwise needed to mitigate industrial hygiene issues.

Table 1 below lists breakage results comparing conditioned fertilizergranules conditioned with an aqueous conditioning agent in the form ofwater in weight percent to unconditioned fertilizer granules. In thisexample, the base fertilizer was monoammonium phosphate and the breakagewas measured.

In particular, an accelerated performance measurement procedure used tomeasure this data consists of the following steps: (1) Initiallyuntreated fertilizer granules are split (with a riffler) to maintaincomparable fractions; (2) The baseline granules are not treated with anaqueous conditioning agent while the remaining granules coated withdifferent experimental treatments of different amounts of aqueousconditioning agent; (3) The coated samples are stored under controlledenvironmental conditions reflecting potential product transportation andstorage conditions; and (4) The effectiveness of dust control ismeasured after several (2, 4, 6, 8) weeks. To measure effectiveness ofdust control, samples are removed from the environmental chamber andexposed to a controlled energy input to simulate product handling. Dustsized particles from each sample are then extracted and the dust levelis determined by mass difference. The reduction percentage is calculatedas a percent change (in this case reduction) from the dust generation ofthe baseline samples.

TABLE 1 Breakage results Typical Conditioning agent added dustgeneration Optimal dust generation (% of fertilizer weight) reductionreduction 2% 30% 55% 3.5%   55% 80% 5% 60% 85%

In other embodiments, such surface treatments and/or incorporation ofadditives or agents by the above methods may result in reduced cakingtendencies by means of inhibiting chemical and/or physical interactionsbetween granules in storage, during transport, or otherwise.

While the invention is amenable to various modifications and alternativeforms, specifics thereof have been shown by way of example in thedrawings and described in detail. It is understood, however, that theintention is not to limit the invention to the particular embodimentsdescribed. On the contrary, the intention is to cover all modifications,equivalents, and alternatives falling within the spirit and scope of theinvention as defined by the appended claims.

What is claimed is:
 1. A method for conditioning inorganic phosphatefertilizer granules for improved dust control, agricultural benefits, orboth, the method comprising: providing a plurality of inorganicphosphate fertilizer granules in a conditioning vessel, the granuleshaving a surface temperature of about 50° F. to about 250° F.;introducing a quantity of an aqueous conditioning agent into theconditioning vessel in an amount of about 0.1 wt % to about 10 wt % ofthe total weight of the inorganic phosphate fertilizer granules;subjecting the inorganic phosphate fertilizer granules with the aqueousconditioning agent thereon to a mechanical energy exposure by mixing ortumbling the inorganic phosphate fertilizer granules in the conditioningvessel to promote particle to particle interaction; and removingmoisture from the inorganic phosphate fertilizer granules until a finalmoisture content of the fertilizer granules is 0 wt % to about 6.5 wt %of the granules, wherein the aqueous conditioning agent comprises asolution or suspension of water and an agent selected from the groupconsisting of: an acidifying agent comprising citric acid, sulfamicacid, sulfuric acid, phosphoric acid, or combinations thereof; a dryingagent comprising corn starch, wheat starch, or combinations thereof; achelating agent comprising ethylenediaminetetraacetic acid (EDTA),polyethylenimine (PEI), or combinations thereof; and combinationsthereof.
 2. The method of claim 1, wherein the aqueous conditioningagent further comprises a secondary nutrient, a micronutrient, or acombination thereof.
 3. The method of claim 2, wherein the secondarynutrient is selected from the group consisting of: a source of sulfur; asource of calcium; a source of magnesium; and combinations thereof. 4.The method of claim 2, wherein the micronutrient is selected from thegroup consisting of: a source of iron; a source of manganese; a sourceof zinc; a source of copper; a source of boron; a source of molybdenum;a source of chlorine; and combinations thereof.
 5. The method of claim1, wherein introducing the quantity of the aqueous conditioning agentinto the conditioning vessel comprises spraying the aqueous conditioningagent onto the inorganic phosphate fertilizer granules in theconditioning vessel, wherein the aqueous conditioning agent isintroduced at a temperature of about 32° F. to about 800° F.
 6. Themethod of claim 1, wherein the conditioning vessel includes mixingequipment selected from the group consisting of a ribbon blender, paddlemixer, baffles, and combinations thereof.
 7. The method of claim 1,wherein the conditioning vessel comprises a rotating drum such thatapplication of the aqueous conditioning agent is spread evenly over thegranules, and to further induce mechanical interaction between thegranules.
 8. A method for conditioning inorganic phosphate fertilizergranules for improved dust control, agricultural benefits, or both, themethod comprising: providing a plurality of inorganic phosphatefertilizer granules in a conditioning vessel, the granules having asurface temperature of about 50° F. to about 250° F.; introducing aquantity of an aqueous conditioning agent into the conditioning vesselin an amount of about 0.1 wt % to about 10 wt % of the total weight ofthe inorganic phosphate fertilizer granules; subjecting the inorganicphosphate fertilizer granules with the aqueous conditioning agentthereon to a mechanical energy exposure by mixing or tumbling theinorganic phosphate fertilizer granules in the conditioning vessel topromote particle to particle interaction; and removing moisture from theinorganic phosphate fertilizer granules until a final moisture contentof the fertilizer granules is 0 wt % to about 6.5 wt % of the granules,wherein the aqueous conditioning agent comprises a solution orsuspension of water and a biological agent, wherein the biological agentcomprises at least one biological material.
 9. The method of claim 8,wherein the biological material comprises one or more microorganisms.10. The method of claim 9, wherein the microorganism is bacteriaselected from the group consisting of Bacillus, Rhizobium, Azobacter,Azospirillum, and combinations thereof.
 11. The method of claim 9,wherein the microorganism is fungi selected from the group consisting ofAspergillus, Mycorhizzae, Beauveria, Metarhizium, Trichoderma,Saccharomyces, Schizosaccharomyces, Sporobolomyces, Candida,Trichosporon, Rhodosporidium, and combinations thereof.
 12. The methodof claim 8, wherein the biological material is selected from the groupconsisting of metabolites, peptides, lipopetides, hormones, peptidehormones, siderophores, glycopepetides, humates, surfactants, vitamins,enzymes, amino acids, amino acid derivatives, nucleic acids, nucleicacid derivatives, and combinations thereof.
 13. The method of claim 8,wherein the biological material comprises bacteria, fungi, or both, andwherein the biological material is applied to fertilizers or fertilizergranules at a final concentration of about 10³ to about 10¹² CFU/g. 14.The method of claim 13, wherein the biological material is applied tofertilizers or fertilizer granules at a final concentration of about 10⁶to about 10⁹ CFU/g.
 15. The method of claim 8, wherein the biologicalmaterial is sprayed on the fertilizer or fertilizer granules as anaqueous solution, and then dried leaving the biological materialdeposited on the fertilizer or fertilizer granule.
 16. A method forconditioning inorganic phosphate fertilizer granules for improved dustcontrol, agricultural benefits, or both, the method comprising:providing a plurality of inorganic phosphate fertilizer granules in aconditioning vessel, the granules having a surface temperature of about50° F. to about 250° F.; introducing a quantity of an aqueousconditioning agent into the conditioning vessel in an amount of about0.1 wt % to about 10 wt % of the total weight of the inorganic phosphatefertilizer granules; subjecting the inorganic phosphate fertilizergranules with the aqueous conditioning agent thereon to a mechanicalenergy exposure by mixing or tumbling the inorganic phosphate fertilizergranules in the conditioning vessel to promote particle to particleinteraction; and removing moisture from the inorganic phosphatefertilizer granules until a final moisture content of the fertilizergranules is 0 wt % to about 6.5 wt % of the granules, wherein theaqueous conditioning agent consists of water.